List.FilterByBoolMask

This takes a list of Booleans (true and false values) as a mask input, and another list as the ‘list to filter’. It then outputs an in list (where the Boolean result was true), and an out list (where the Boolean result was false). This works most reliably with matching length input lists.

String.Contains

This allows you to search a string for the existence of another string fragment inside it. It optionally can ignoreCase (default is to do a Case Sensitive search). It can work with List input at the str Input connection, and it outputs a boolean true / false list that can be used to filter other results.